It's a lesson that Irvine, some 400 miles south, will learn as it begins development of the former El Toro Marine base, anchored in the heart of Orange County.

"You have to have a lot of patience, and you have to have a good plan and stick to it, within reason," said Councilman Gary Cloutier, a San Francisco attorney who moved to Vallejo eight years ago seeking refuge from the Bay Area bustle.

His restored 1898 Victorian mansion sits atop a knoll overlooking the shipyard, which was closed in 1996. From his back patio, he has a perfect view across the narrow strait as the setting sun illuminates a junked warehouse, glinting from rows of grimy windows. Crews built submarines in the massive structure, just one more job in the life of a base that began in 1854 with horses and cannons and ended its days handling nuclear subs and warheads.

The 5,223 acres of former Navy property is owned by Lennar Mare Island, a subsidiary of Lennar Corp., chosen by Vallejo in 1997 as the site's master developer. In 2002, Lennar took title to 650 acres on the island, where it says it will build homes, shops, restaurants and businesses. The company got the land free but promised to invest $260 million in streets and utilities, historic preservation and building renovation.

The project is a striking parallel to Lennar's interests to the south: the mothballed 3,718-acre former Marine Corps Air Station at El Toro, which the developer won at auction in February for $649.5 million. Like Mare Island, El Toro is an enormous piece of land riddled with contamination but holding great potential.

In Vallejo, residents are banking that the property's development will revitalize a town that had found financial stability and its civic identity in a shipyard that stared back at them from Mare Island. In Orange County, planners hope to create a parkland core within a ring of homes and businesses, on a par with San Diego's Balboa Park or New York's Central Park.

For Lennar, closed military bases have become a cottage industry. Since acquiring the Mare Island acreage, Lennar has won bids to develop homes and offices at the closed Hunter's Point Naval Annex in San Francisco and built 16 million square feet of industrial and office space on portions of March Air Reserve Base near Riverside. It is also negotiating to build on the former Treasure Island Naval Base in San Francisco.

The spending spree is according to plan. Company officials deliberately eyed closed naval bases in California because of their attractive locations. Though the process has been slow and complicated, thanks to toxic contamination and dissension over how the land should be used, the long-term payoff could be handsome.

"Mare Island was our first deal, and the first ones are always slower because everyone is going through a learning curve -- even the Navy," said Emile Haddad, Lennar's regional president for California. So far, about 2,000 people work on the island in 70 businesses -- a fifth of the expected total.

Mare Island and El Toro will be lightly developed, with much of the land set aside for wildlife habitat and open space. Lennar will build on about 900 acres of the 5,223-acre Mare Island (it will receive 250 more acres in July). At El Toro, about 1,200 of 4,700 acres will be commercially developed.

One clear difference lies in what the Navy left behind: Lennar inherited some 502 historic "resources" on Mare Island, including a 1901 chapel with Tiffany stained-glass windows and a 1911 dry dock, from which Jupiter -- the first Navy aircraft carrier -- was launched. At El Toro, which opened in 1943, there isn't much to be saved.

The reconstruction efforts at the former bases face hurdles more complex than most developments. It will take years, for instance, to clean up the environmental mess from decades of military operations. Residents, meanwhile, want assurances that progress is made without draining local government funds.

Watching more than eight years pass without much to show has been frustrating, some Vallejo residents say. Mare Island's eastern edge, a stone's throw from the city's redesigned waterfront and public ferry, has the same gritty look it did for decades. Shipyard businesses lease space in an area planned as a waterfront district of restaurants and tourist boutiques.

"I think someone with big money has gone in and is going to make bigger money," groused Clair Crawford, a former Idaho resident who moved to Vallejo 15 years ago. He opened his used-car dealership in town a year before the base closed, then watched business evaporate as the Navy -- and the local economy it fueled -- left town.